Analysts and pundits ponder the impact of 64-bit tablet on consumer, business laptop industry

Some analysts and pundits have begun calling Apple's iPad Air a PC replacement, raising the stakes in the tablet vs. laptop war.

The iPad Air goes on sale tomorrow, and unlike the four earlier iterations, is powered by a 64-bit processor. And while it retains the original 9.7-in. screen, it's 29% lighter and 20% thinner than its immediate predecessor.

"I'm convinced that the iPad Air is the perfect personal computer for the masses," asserted Ben Bajarin, an analyst at Creative Strategies, in a post to his firm's Techpinions.com website Tuesday. "The iPad has become as versatile as any personal computer on the market."

Others chimed in with similar impressions.

"For anyone who doesn't truly take advantage of the capabilities in Mac OS X (or Windows) that aren't available in iOS, the iPad Air is a superior portable computer to a laptop in nearly every way," wrote John Gruber on his popular Daring Fireball website.

There were caveats, naturally, ranging from lack of a physical keyboard (Gruber) to workplace focus (Bajarin). But the theme was clear: The 64-bit A7 system-on-a-chip (SoC), the longer-than-notebook battery life, the free iWork productivity apps and the much-lighter-than-laptop form factor make the iPad Air a tablet that can compete with a traditional notebook for most people.

It's a bold proposition, one not widely expressed about earlier versions of the iPad, or about few tablets for that matter other than Microsoft's Surface line and the often-radical "hybrid," "convertible" or "2-in-1" designs dreamed up by Microsoft's hardware partners. And it's one not everybody agrees with.

"In every survey we've done, overwhelmingly tablet owners tell us that they didn't buy a tablet as a replacement for their notebook," said Tom Mainelli, an analyst with IDC. "They admit that they use a notebook less, but one-to-one replacement, that really isn't happening."

The numbers support that. While tablets are generally credited -- or blamed -- for the stagnation, then contraction, of traditional PC shipments, sales of the former have not depressed sales of the latter on a 1-for-1 basis. If they had, the PC industry would be struggling to simply survive: According to IDC, tablet shipments in the third quarter equaled 58% of the number of PCs shipped during the same period.

But neither Mainelli's IDC or rival Gartner have been able to quantify the notebook cannibalization rate, or as Mainelli put it, "Come up with a formula that says X minus Y equals Z."

It's not that easy. "To be honest, we've tried to put the numbers together, but it's just more complicated than 'I buy a tablet and it replaces a notebook,'" said Mainelli.

He was dubious that tablets, even the iPad Air, were ready to step into laptops' shoes across the board -- particularly in business, where Microsoft is entrenched in large part because of its Office suite. "PCs in businesses are not going away," Mainelli said.

Echoing Mainelli was Carolina Milanesi of Gartner. "It's not because of the form factor," said Milanesi of tablets and enterprise reluctance to swap them for notebooks. "It's because it's iOS. There's still a lot pulling to Microsoft from an application point of view."

Still, notebook-for-tablet swapping is the future, maintained Mainelli, and even if the iPad Air isn't the tipping point, it has moved the needle. "The 64-bitness of the iPad Air lends itself to this," he said.

True, assuming things work out as many analysts believe. They've viewed the A7 processor, and the underlying promise of more sophisticated apps, as an important duo for development of more powerful and memory-intensive tablet productivity apps.